Display technologies using encapsulated electrophoretic particles, multichromal beads and liquid crystals are commonly referred to as electronic paper. A group of encapsulated bichromal beads, cylinders, crystals or other bichromal or multichromal particles can be dispersed in an elastomeric sheet swollen by a fluid and positioned atop a conductive substrate. The particles, fluid and substrate are covered with a transparent layer such as glass or plastic and a transparent conductive material such as indium tin oxide, and are sealed to form a display material. The particles in the display material rotate in response to an electric or magnetic field that is applied to the conductive substrate. Such materials have been described in, for example, U.S. Pat. Nos. 4,126,854 to Sheridon and 4,143,103 to Sheridon, the disclosures of each of which are incorporated herein by reference in their entirety.
Bichromal displays have numerous advantages over conventional electrically addressable visual displays, such as LCD and CRT displays. In particular, they are suitable for viewing in ambient light, they retain an image indefinitely in the absence of an applied electric field, and they can be made lightweight, flexible, foldable, and with many other familiar and useful characteristics of ordinary writing paper. Thus, at least in principle, they are suitable both for display applications and for so-called electric paper or interactive paper applications, in which they serve as an electrically addressable, reusable substitute for ordinary paper.
Outdoor advertising displays are common. Conventional outdoor advertisements on public transportation systems are typically displayed in a static form, such as painted on the exterior of a bus or the interior of a subway. As such, these advertisements cannot be dynamically modified or updated. Moreover, the cost of replacing such advertisements is high. In addition, such advertisements cannot be dynamically updated based on proximity to an advertiser.
The disclosure contained herein describes the methods of resolving one or more of the problems discussed above.